Recently, in order to provide a wireless charging function to an electronic device such as a smart phone, a tablet personal computer (PC), and the like, there is much research being conducted and developments being made. Accordingly, many electronic devices, which are currently released or are due to be released, are starting to support the wireless charging function of an electromagnetic induction scheme, a resonance scheme, or the like.
Wireless charging methods may be largely divided into the electromagnetic induction scheme and the resonance scheme. The electromagnetic induction scheme has a problem of a limited distance in spite of a small power loss. The resonance scheme has a relatively high power loss rate but has an advantage of a greater distance and charging a plurality of electronic devices. The resonance scheme corresponds to a method of maximizing a wireless transmission efficiency of energy through resonance between antennas of a power supply device and a power reception device. To this end, the power supply device synchronizes a resonant frequency with the power reception device to generate a resonant channel and transmits wireless power through the resonant channel.
However, wireless charging has a problem in that, when there is a hindrance in a path through which power is transmitted or a charging distance is far, a charging efficiency is significantly reduced. Further, in the wireless charging, a user may be exposed to electromagnetic waves for the wireless charging and thus affected by the electromagnetic waves.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.